Geology Commons^™

Pseudokarst Of East Texas: Geomorphic Features And Evolution [Abstract], Kevin W. Stafford, Melinda G. Shaw-Faulkner, Wesley A. Brown

Faculty Presentations

No abstract provided.

Geochemical Spatial Variability Of The Colorado River Associated With Karst Springs, Colorado Bend State Park, Central Texas [Abstract], Katie Mitchell, Sherri Dornak, Kevin W. Stafford

Faculty Presentations

No abstract provided.

An Extraordinary Example Of Photokarren In A Sandstone Cave, Cueva Charles Brewer, Chimantá Plateau, Venezuela: Biogeomorphology On A Small Scale, Joyce Lundberg, Donald A. Mcfarlane, Charles Brewer-Carias

WM Keck Science Faculty Papers

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation. …

A Unique Population Of Cave Bears (Carnivora: Ursidae) From The Middle Pleistocene Of Kents Cavern, England, Based On Dental Morphometrics, Donald A. Mcfarlane, Martin Sabol, Joyce Lundberg

WM Keck Science Faculty Papers

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from …

A Geographic Information Systems Approach To The 19th Century Excavation Of Brixham Cavern, Devon, England, Donald A. Mcfarlane, Joyce Lundberg, Warren Roberts

WM Keck Science Faculty Papers

The oldest known spatially-explicit archaeological excavation, conducted in Brixham cave, Devon, in 1858, is reconstructed using geographic information systems technology. Two dimensional plots of individual fossil taxa and flint artefacts demonstrate the utility of the technique for elucidating taphonomy and palaeobiology. The cave served as a den for hibernating brown bears, as a den for hyena and cave lion, and as a reliquary for their prey.

Climate In The Southern Sawatch Range And Elk Mountains, Colorado, U.S.A., During The Last Glacial Maximum: Inferences Using A Simple Degree-Day Model, Keith A. Brugger

Geology Publications

Equilibrium-line altitudes (ELAs) were determined from reconstructions of 22 paleoglaciers at their extent during the local last glacial maximum (LGM) using the accumulation-area method. LGM ELAs thus derived ranged from 2980 to 3560 m and follow a statistically significant regional trend of rising ~4.5 m km^-1 to the east. Two approaches using a degree-day model were used to infer LGM climate by finding plausible combinations of temperature and precipitation change that (1) would be required to lower ELAs to their mean LGM values in both the Taylor Park/eastern Elk Mountains region and western Elk Mountains, and (2) provide steady-state …

A Study Of Fold Characteristics And Deformation Style Using The Evolution Of The Land Surface: Zagros Simply Folded Belt, Iran, Caroline M. Burberry, John W. Cosgrove, Jian-Guo Liu

Department of Earth and Atmospheric Sciences: Faculty Publications

Deformation styles within a fold-thrust belt can be understood in terms of the spatial organization and geometry of the fold structures. In young fold-thrust belts such as the Zagros, this geometry is reflected topographically by concordant landform morphology. Thus, the distribution of deformation structures can be characterized using satellite image analysis, digital elevation models, the drainage network and geomorphological indicators. The two distinct fold types considered in this study (fault-bend folds and detachment folds) both trending NW-SE, interact with streams flowing NE-SW from the High Zagros Mountains into the Persian Gulf. Multiple abandoned stream channels cross fault-bend folds related to …

Composition And Structure Of The San Andreas Fault Observatory At Depth (Safod) Phase Iii Whole-Rock Core: Implications For Fault Zone Deformation And Fluid-Rock Interactions, Kelly Keighley Bradbury, James P. Evans

Geosciences Presentations

We examine the composition and texture of whole-rock core from ~ 3 km depth in the San Andreas Fault Observatory at Depth (SAFOD) borehole, which provides a unique opportunity to characterize in situ rock properties of the near-fault environment, and how these properties vary in an area where deformation is accommodated by aseismic creep and high-rates of microseismicity. Detailed petrography and microstructural analyses coupled with X-Ray Diffraction and X-ray Fluorescence techniques are used to describe composition, alteration, and textures.

All samples record multiple generations of cataclastic deformation in a complexly deformed and altered sequence of fine-grained sheared rocks. Localized shears …

Geologic Map Of The Nez Perce Drainage Basin, Southwestern Montana, Rose Aimee Feinstein

Inquiry: The University of Arkansas Undergraduate Research Journal

A geologic map of the Nez Perce drainage basin in southwestern Montana offers an understanding of the developing paleotopography of the area following the Laramide orogeny, ca. 65 ma. In this project, a small drainage basin was studied in detail, focusing on the geomorphology, structure, lithology, and ages of the various rock units. Based on the results of these studies and the relationships found among four major gravel units mapped within the basin, the basin development was approximated. The youngest unit is a fine-grained (mean diameter = 8.23 cm) channel deposit within Nez Perce Creek, sourced from within the basin, …

A Two-Dimensional, Linear–Elastic Model To Explain Radial Extensional Fractures, Pantheon Fossae, Caloris Basin, Mercury, Brianne Mcdonough

Undergraduate Review

In this study, two-dimensional linear elasticity theory is used to model the lithospheric stress field that produces radial extensional fractures observed at Pantheon Fossae in the Caloris Basin of Mercury. These fractures were imaged by the MESSENGER mission flyby of Mercury on January 14, 2008 and show radial fractures extending outward from a 40-kilometer impact crater named Apollodorus. Recent studies have proposed several different mechanisms to explain these fractures, including magmatic processes, central basin uplift, and stresses produced by the formation of the impact crater itself.

Constructing A Flash Flood Climatology Of The Appalachian Mountains: Comparison Of Eastern Kentucky And West Virginia Summer Time Rain Events, Jane Marie Wix

Mahurin Honors College Capstone Experience/Thesis Projects

The Appalachian Mountains are subject to flash floods due to interactions between complex terrain and frequent rainfall. Previous studies have shown that a number of environmental factors can trigger flash floods, which can leave behind a variety of outcomes. However, there is a lack of research concerning flash floods in the Appalachian region. This study addresses these concerns by examining summer (June-August) rainfall frequency and intensity in connection with flash floods in the Appalachian region of eastern Kentucky and West Virginia during 1995-2005. Flash floods were identified using the National Climatic Data Center’s (NCDC) Storm Database. Radar estimated rainfall data …

Regional Vs. Local Impact Of Wind On Glaciers In The Andes Mountains, Derek Ferris

Undergraduate Review

Northern Peru will face critical water resource issues in the near future as permanent ice in the Andes Mountains continues to rapidly melt. Ironically, the melt-water from these glaciers supports the culture of 100s of thousands of people living at lower elevations, particularly during the dry season, and predictions suggest some glaciers may be gone in less than 100 years. The impact of local warming of “U” shaped valleys running down the dryer western slope of the Andes range is largely disregarded in current climate model predictions because of the complexity of simulating the complex topography. Studies that compare the …

An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, Peter-Jon A. Waddell, A K. Gardner, P Hennig

Technical Bulletins

The inventory and condition survey of the Western Australian part of the Nullarbor region, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 2005 and 2007, describes and maps the natural resources of the region. This survey report provides a baseline record of the existence and condition of the area's natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The Nullarbor region has …

Geology Of The Gordon Natural Area: A Service-Learning Investigation By Students In Ess 405, Petrology, Fall 2009, Leeann Srogi

Gordon Natural Area Geology Studies Documents

No abstract provided.

Geochemical And Mineralogical Evidence For Sahara And Sahel Dust Additions To Quaternary Soils On Lanzarote, Eastern Canary Islands, Spain, Daniel R. Muhs, James Budahn, Gary Skipp, Joseph M. Prospero, Deanna Patterson, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

Africa is the most important source of dust in the world today, and dust storms are frequent on the nearby Canary Islands. Previous workers have inferred that the Sahara is the most important source of dust to Canary Islands soils, with little contribution from the Sahel region. Soils overlying a late Quaternary basalt flow on Lanzarote, Canary Islands, contain, in addition to volcanic minerals, quartz and mica, exotic to the island!s bedrock. Kaolinite in the soils also likely has an exotic origin. Trace-element geochemistry shows that the soils are derived from varying proportions of locally derived basalt and African dust. …

Development And Application Of A Pollen-Based Paleohydrologic Reconstruction From The Lower Roanoke River Basin, North Carolina, Usa, Debra Willard, Christopher Bernhardt, Roger Brown, Bryan Landacre, Philip A. Townsend

United States Geological Survey: Staff Publications

We used pollen assemblages to reconstruct late-Holocene paleohydrologic patterns in floodplain deposits from the lower Roanoke River basin (North Carolina, southeastern USA). Using 120 surface samples from 38 transects, we documented statistical relationships between pollen assemblages, vegetation, and landforms. Backswamp pollen assemblages (long hydroperiods) are dominated by Nyssa (tupelo) and Taxodium (cypress) and have high pollen concentrations. Sediments from elevated levees and seasonally flooded forests (shorter hydroperiods) are characterized by dominant Pinus (pine) pollen, variable abundance of hardwood taxa, and low pollen concentrations. We apply the calibration data set to interpret past vegetation and paleohydrology. Pollen from a radiocarbon-dated sediment …

Plains Co2 Reduction (Pcor) Partnership Atlas, Wesley D. Peck, Katherine K. Anagnost, Barry W. Botnen, Lisa S. Botnen, Daniel J. Daly, Charles D. Gorecki, Megan M. Grove, John A. Harju, Melanie D. Jensen, Michael L. Jones, Steven A. Smith, James A. Sorensen, Edward N. Steadman, Stephanie L. Wolfe, Andrea T. Mcnemar, John T. Litynski, Sean I. Plasynski

EERC Maps and Infographics

The Plains CO₂ Reduction (PCOR) Partnership Atlas, revised 3rd edition, introduces global climate change and a regional profile of CO₂ sources and potential sinks across central North America. Carbon storage offers a promising set of technologies through which CO₂ can be stored for long periods of time.

Crustal Thickness Of The Marie Byrd Land Dome And Its Implications, Joshua Svaldi

Undergraduate Honors Theses

This study focuses on the crustal thickness of the Marie Byrd Land Dome (MBLD) in West Antarctica, which is a region of high elevation in proximity to a zone of extension and crustal thinning. We use the H-K receiver-function stacking method developed by Zhu and Kanamori (2000) to analyze the incoming seismic waves of tcleseismic events. The aim of the project is to determine whether or not the MLBD is in isostatic equilibrium. Values for crustal thickness at the Mt. Patterson site, along the western extremity of MBLD, are 28-31 km, while theoretical calculations have yielded a thickness of 33.5 …

Planning The Future Of Geocybereducation, Jeffrey G. Ryan, Susan Eriksson

Geology Faculty Publications

No abstract provided.

Sources And Occurrences Of Nonpoint-Source Chemicals In Groundwater, Jackson Purchase Region, Kentucky: Data Report, E. Glynn Beck

Information Circular--KGS

Groundwater from the Jackson Purchase Region was sampled to investigate possible contamination by nonpoint-source chemicals. Conclusions drawn from the resulting data and methodology can be found in “Sources and Occurrences of Nonpoint-Source Chemicals in Groundwater, Jackson Purchase Region, Kentucky,” Kentucky Geological Survey Report of Investigations 22 (series 12), by R.S. Fisher and E.G. Beck.

Geology Of Central Eleuthera, Bahamas: A Field Trip Guide, Pascal Kindler, John E. Mylroie, H. Allen Curran, James L. Carew, Douglas W. Gamble, Thomas A. Rothfus

Geosciences: Faculty Publications

See other Smith authored Field Trip Guides of Gerace Research Centre.

Enigmatic Structures On Upper Pleistocene Laminar Caliche Surfaces Of The Bahamas: Animal, Vegetable, Or Mineral?, H. Allen Curran

Geosciences: Faculty Publications

Trace fossils are a common and important component of most Quaternary carbonate rock units of the Bahamas and other, similar tropical carbonate regions. In the Bahamas, the Pleistocene-Holocene boundary is typically marked by a calichified paleosol horizon that formed on the exposed limestone surfaces of the islands during the time of lowered sea level of the Last Glacial. On the north coast of San Salvador Island, an extensive horizontal surface of laminar caliche is exposed at Singer Bar Point and to the west. This surface formed on carbonate eolianite of Late Pleistocene (Eemian) age and is overlain by Holocene eolianite. …

Ground Penetrating Radar Investigations In Upper Kama Potash Mines, Oleg N. Kovin

Doctoral Dissertations

"An understanding of the structure and state of the rock mass surrounding underground openings in the potash mines is critically important for safe mining, planning the methods of extraction of an orebody, and preventing the influx of ground water. Continuous common offset ground penetrating radar (GPR) data were acquired in the potash mine operated by the Joint Stock Company (JSC) "Silvinit" (Russia) as part of an investigation of both pre-existing fractures exposed by mine workings and other anomalous geological structures. During the course of GPR investigation, the electrical properties of salt-bearing units were determined, site-specific data acquisition techniques and object-oriented …

Absorption And Biotransformation Of Polybrominated Diphenyl Ethers De-71 And De-79 In Chicken (Gallus Gallus), Mallard (Anas Platyrhynchos), American Kestrel (Falco Sparverius) And Black-Crowned Night-Heron (Nycticorax Nycticorax) Eggs, Moira A. Mckernan, Barnett A. Rattner, Jeff S. Hatfield, Robert C. Hale, Mary Ann Ottinger

United States Geological Survey: Staff Publications

We recently reported that air cell administration of penta-brominated diphenyl ether (penta-BDE; DE-71) evokes biochemical and immunologic effects in chicken (Gallus gallus) embryos at very low doses, and impairs pipping (i.e., stage immediately prior to hatching) and hatching success at 1.8 µg g^-1 egg (actual dose absorbed) in American kestrels (Falco sparverius). In the present study, absorption of polybrominated diphenyl ether (PBDE) congeners was measured following air cell administration of a penta-BDE mixture (11.1 lg DE-71 g^-1 egg) or an octa-brominated diphenyl ether mixture (octa BDE; DE-79; 15.4 lg DE-79 g^{- …}

Mineralization In The San Juan Mountains, Colorado, William M. Sheriff

Open Access Theses & Dissertations

none

Assessment Of Row Crop, Alfalfa, And Pasture Field Practices On Groundwater Quality In An Upland Bedrock Setting, Henderson County, Kentucky: Report Of Soil- And Water-Quality Data, E. Glynn Beck, James S. Dinger, John H. Grove, Eugenia Pena-Yewtukhiw

Information Circular--KGS

An assessment of how present agricultural practices have influenced shallow groundwater and soil quality was conducted on a 540-acre farm in north-central Henderson County. Groundwater- and soil-quality data were collected from row crop (corn and soybean), alfalfa, and pasture fields. In addition to the field settings, groundwater and soil data were collected from the existing farmyard and an abandoned feedlot. Groundwater samples were analyzed for pH, specific conductance, temperature, oxidation-reduction potential, metals, anions, nutrients, herbicides, and various isotopes. Soil samples were analyzed for pH, bioavailable phosphorus, potassium, calcium, magnesium, zinc, organic matter, total nitrogen, and inorganic nitrogen (nitrate-N). Soil- and …

Development Of A Spectral 2-D Fast Fourier Transform Analysis For Sand Ripple Morphology Interpretation, Christopher M. Englert

Honors Theses

A MATLAB-based 2-Dimensional Fast Fourier Transform spectral analysis is developed and tested for its applicability to bedform morphology and hydrodynamic data from a hydrodynamically complex field site. The aspects of the procedure tested are (1) the use of an 8 sub-region arrangement for analysis versus five other arrangements, (2) the procedure for averaging the wavelength-and-orientation outputs from each sub-region to produce a single representative value for each image, (3) methods for eliminating and/or filtering poor quality data, and (4) the procedural steps in the spectral analysis that can appropriately incorporate automation versus manual involvement and interpretation. The automated technique is …

Late Permian Paleoenvironmental Factors Expounded Through Analysis Of A Forest-Floor Paleosol Profile, Karoo Basin, South Africa, Cassi Knight

Honors Theses

Beaufort Group paleosols from the Karoo Basin, South Africa, record the paleoenvironmental conditions that existed prior to and after the Permian-Triassic extinction event. Paleosol exposures from Wapadsberg Pass, Eastern Cape Province, represent a well- preserved forest-floor litter overlying an interpreted inceptisol, a condition unique to the basin. Vegetation that colonized this landscape included a canopy of the gymnosperm Glossopteris and an understory of sphenopsids (Phyllotheca and Trizygia). Wapadsberg Pass paleosol sites were sampled for petrographic and geochemical analyses to constrain interpretations of Late Permian paleoenvironmental conditions that existed ~ 70 m below the Permian-Triassic Boundary (PTB). This project focuses on …

Causes Of Tropical Atlantic Paleo-Salinity Variation During Periods Of Reduced Amoc, Xiuquan Wan, Ping Chang, Matthew W. Schmidt

OES Faculty Publications

During periods of reduced Atlantic meridional overturning circulation (AMOC) associated with a freshening of northern North Atlantic surface water, paleo proxy records indicate a corresponding surface salinity increase over the entire tropical Atlantic. Although latitudinal-shifts in the mean position of the Atlantic Intertropical Convergence Zone (ITCZ) can explain certain features of the paleo salinity reconstructions, this mechanism does not offer an explanation for the reconstructed basin-wide paleo-salinity response to AMOC change. Here, we present new results from general circulation model simulations that suggest the sea surface salinity (SSS) increase in the tropical north Atlantic during periods of weakened AMOC is …

What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano

Environmental Science and Geology Faculty Research Publications

Using an Integrated Assessment (IA) framework, we consolidated and utilized existing data from the Detroit River to develop models that both identify possible drivers of elevated fish contaminant body burdens, and to facilitate a more risk-based approach of tissue trigger-levels for consumption advisories. This integrated assessment approach was particularly useful for consumption advisories as it provided the ability to integrate and organize complex data in a manner that can help inform management decisions. In addition, the IA framework explicitly fosters collaboration and participation of multiple interested groups. We have capitalized on this component of IAs, by seeking the active participation …